Field of the Invention
The present invention relates to a thermal energy recovery device for recovering exhaust heat.
Description of the Related Art
Conventionally, thermal energy recovery devices for recovering thermal energy such as geothermal water are known, and a representative thereof is a binary generator.
Japanese Patent Application Laid-Open No. H11-107906 discloses an example of a binary power generation system. The binary power generation system has a closed loop which sequentially connects an evaporator, a screw turbine and a condenser and circulates a working medium. In a bypass path which connects the upstream side and the downstream side of the screw turbine in the closed loop, a pressure regulating valve is provided. The pressure regulating valve opens when a detection value of a pressure sensor provided on the upstream side of the screw turbine in the closed loop exceeds a set value. Between the evaporator and the condenser in the closed loop, an automatic valve is provided. The automatic valve ordinarily opens, and is set so as to automatically close when the power is turned off in case of some sort of trouble. When the automatic valve closes at the time of the power-off, the working medium is not supplied to the evaporator, so that, even if a heat source fluid is supplied to the evaporator, evaporation of the working medium in the evaporator does not continue, and operation of a safety valve provided in the closed loop due to an abnormal pressure rise is suppressed.